Country/ies of origin | France |
---|---|
Operator(s) | CNES |
Type | Civilian |
Status | Operational |
Constellation size | |
Nominal satellites | 0 (ground transmitters only) |
First launch | 1990 |
DORIS is a French satellite system used for the determination of satellite orbits (e.g. TOPEX/Poseidon) and for positioning. The name is an acronym of "Doppler Orbitography and Radiopositioning Integrated by Satellite" or, in French, Détermination d'Orbite et Radiopositionnement Intégré par Satellite.
Ground-based radio beacons emit a signal which is picked up by receiving satellites. This is in reverse configuration to other GNSS, in which the transmitters are space-borne and receivers are in majority near the surface of the Earth. A frequency shift of the signal occurs that is caused by the movement of the satellite ( Doppler effect). From this observation satellite orbits, ground positions, as well as other parameters can be derived.
DORIS is a French system which was initiated and is maintained by the French Space Agency ( CNES). It is operated from Toulouse.
The ground segment includes about 50-60 ground stations, equally distributed over the Earth and ensure a good coverage for orbit determination. For the installation of a beacon only electricity is required because the station only emits a signal but does not receive any information. DORIS beacons transmit to the satellites on two UHF frequencies, 401.25 MHz and 2036.25 MHz.
There are two active DORIS stations in Australia: [1]
The best known satellites equipped with DORIS receivers are the altimetry satellites TOPEX/Poseidon, Jason-1, OSTM/Jason-2, Jason-3, and Sentinel-6 Michael Freilich. They are used to observe the ocean surface as well as currents or wave heights. DORIS contributes to their orbit accuracy of about 2 cm.
Other DORIS satellites are the Envisat, SPOT, HY-2A and CryoSat-2 satellites. [2]
Apart from orbit determination, the DORIS observations are used for positioning of ground stations. The accuracy is a bit lower than with GPS, but it still contributes to the International Terrestrial Reference Frame (ITRF). [3]
{{
cite web}}
: CS1 maint: multiple names: authors list (
link)
Country/ies of origin | France |
---|---|
Operator(s) | CNES |
Type | Civilian |
Status | Operational |
Constellation size | |
Nominal satellites | 0 (ground transmitters only) |
First launch | 1990 |
DORIS is a French satellite system used for the determination of satellite orbits (e.g. TOPEX/Poseidon) and for positioning. The name is an acronym of "Doppler Orbitography and Radiopositioning Integrated by Satellite" or, in French, Détermination d'Orbite et Radiopositionnement Intégré par Satellite.
Ground-based radio beacons emit a signal which is picked up by receiving satellites. This is in reverse configuration to other GNSS, in which the transmitters are space-borne and receivers are in majority near the surface of the Earth. A frequency shift of the signal occurs that is caused by the movement of the satellite ( Doppler effect). From this observation satellite orbits, ground positions, as well as other parameters can be derived.
DORIS is a French system which was initiated and is maintained by the French Space Agency ( CNES). It is operated from Toulouse.
The ground segment includes about 50-60 ground stations, equally distributed over the Earth and ensure a good coverage for orbit determination. For the installation of a beacon only electricity is required because the station only emits a signal but does not receive any information. DORIS beacons transmit to the satellites on two UHF frequencies, 401.25 MHz and 2036.25 MHz.
There are two active DORIS stations in Australia: [1]
The best known satellites equipped with DORIS receivers are the altimetry satellites TOPEX/Poseidon, Jason-1, OSTM/Jason-2, Jason-3, and Sentinel-6 Michael Freilich. They are used to observe the ocean surface as well as currents or wave heights. DORIS contributes to their orbit accuracy of about 2 cm.
Other DORIS satellites are the Envisat, SPOT, HY-2A and CryoSat-2 satellites. [2]
Apart from orbit determination, the DORIS observations are used for positioning of ground stations. The accuracy is a bit lower than with GPS, but it still contributes to the International Terrestrial Reference Frame (ITRF). [3]
{{
cite web}}
: CS1 maint: multiple names: authors list (
link)